It has been the objective of many fluid dispensing systems to deliver fluid products in the form of a spray. Such a delivery system is one of the most effective in terms of producing a relatively uniform coating of fluid on a target surface. When a consumer product can be applied in an atomized spray form, the consumer can perceive tangible benefits such as reduced usage of product, reduced messiness in the application of the product, and less opportunity for contamination. Manually actuated, hand holdable, pump spray delivery systems are convenient for household consumers to use and are preferred by such users since they can be held with one hand while the atomized spray is directed toward the target surface. Thus, the development of such spray delivery systems having a nozzle which can deliver a wide range of products, such as hair sprays, cosmetics, vegetable oils, and the like, in an atomized spray has significant commercial value.
A common problem with pump spray delivery systems is that solid particles individually or in agglomerated groups can cause clogging of the small passages in the nozzles. It is therefore desirable to have a nozzle capable of clearing the clog itself. Such a nozzle could contain a separate cleaning mechanism, but such mechanisms typically require some separate action on the part of the user or the incorporation of extra parts. Ideally, it is desirable that a nozzle be designed wherein at the onset of clogging, the nozzle initiates a self cleaning action.
Another problem associated with many pump spray delivery systems is startup and shutoff of the fluid product spray during the beginning and end of an actuation cycle. When hydraulic pressure and flow rate are building up or tapering off, most nozzles tend to poorly disperse the product or tend to eject the product in a slow moving concentrated stream. This results in messiness and product waste, as well as being inconvenient to the user. One way to solve this problem is by utilizing a nozzle which is normally maintained closed and that requires a minimum hydraulic pressure in order to open. Such a precompression function not only provides the additional benefit of preventing product flow prematurely through the nozzle, but can also avoid inadvertent dispensing due to differential pressures between the inside and outside of the container. Such a nozzle can thus serve as a shipping seal. Unfortunately, a normally closed nozzle can also prevent or inhibit priming of the pump. Therefore, a nozzle that provides a balance between shutoff and priming can be very beneficial by providing enhanced reliability as well as improved performance.
Some liquid dispensing nozzles designed for industrial use have attempted to resolve some of the aforementioned problems by utilizing a deformable outlet to achieve the goal of self cleaning without extra parts or mechanisms. U.S. Pat. No. 3,214,102 issued to Meyer discloses, for example, a deformable nozzle that produces a concentrated stream of liquid, not an atomized spray. While some other industrial nozzles produce atomized sprays, most do so by utilizing rigid nozzles. U.S. Pat. No. 5,323,963 issued to Ballu discloses, for example, an elastically deformable nozzle having a discharge opening that is normally open wherein the geometry of the exit region is adjusted by a movable rigid retaining collar. Such a nozzle, however, is not fully self cleaning since the geometry is controlled by the rigid restraining collar.
Another sprayer designed for industrial use in spraying anti-coking substances is disclosed in USSR Inventor's Certificate SU 1729602 A1. This sprayer, for example, includes a nozzle made of an elastic material having spherical inner and outer surfaces and a slot-shaped exit orifice. The inner and outer spherical surfaces of the nozzle are concentric and the ratio of the diameter of the inner spherical surface of the nozzle to the square of the thickness of its wall is from 3.0 to 3.7. One problem with this type sprayer is that it produces streams of liquids and not an atomized spray. U.S. Pat. No. 3,286,931 issued to Webb, and U.S. Pat. No. 5,074,471 issued to Baumgarten et al., disclose, for example, normally closed, self cleaning orifices that are also designed to produce concentrated streams of liquid and not an atomized spray. Unfortunately, none of these aforementioned pump spray packages have provisions for quick shut off of the product stream, well defined atomized spray patterns, or allow for priming of manually actuated pumps.
Some other dispensing systems for consumer products utilize simple flexible diaphragms with center cut slits. Such an atomizer is disclosed in U.S. Pat. No. 3,428,223 issued to Lewiecki which specifies that it is for use with aerosol products. Such an atomizer has been tested using a manually actuated pump with a viscous vegetable oil. When tested in this manner, the Lewiecki atomizer resists clogging and closes when at rest, but the resulting spray pattern is poorly atomized and, as a result, the fluid product is poorly distributed on the target surface. Thus, a nozzle with a pump spray delivery system capable of dispersing a solids laden fluid into a fan shaped atomized spray pattern that also provides a balance between shutoff and priming is not disclosed in the art and would be very beneficial.